Hd newborn

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<ul><li><p>UNIVERSIDAD AUTNOMA DE GUERRERO</p><p> UNIDAD ACDEMICA FACULTAD DE MEDICINAMendoza McGinnis Gema ItzelVillagmez Vlez Julio AndrsArzeta Serrano Laura GabrielaHernndez Barrera MarioENGLISH CLASS: HEMOLYTIC DISEASE OF NEWBORN</p><p>EQUIPO FISIOLOGA.</p></li><li><p>ObjectivesThe student is expected to learn about clinical symptoms, diagnosis, and treatment for hemolytic newborn disease.</p><p>Reinforce everything learned in physiology class by applying a case study.</p><p>Participate in a group dynamic to simplify the learning experience.</p></li><li><p>Antibodies - AnticuerposShortened - acortado Ocurring - ocurriendoAg Glutination - Glutinacion antigenicoInmunogenic - InmunogenicoInvolves - Involucrar</p></li><li><p>Phagocytic - FagociticoBinding - Fristloorn - Microspheocytes - Microfeoscitos. </p></li><li><p>Hemolytic disease of the new born and fetus (HDN) is a destruction of the red blood cells (RBCs) of the fetus and neonate by antibodies produced by the mother</p><p>It is a condition in which the life span of the fetal/neonatal red cells is shortened due to maternal allo-antibodies against red cell antigens acquired from the father</p></li><li><p>Antibodies Five classes of antibodiesIgMIgGIgAIgDIgEBlood groups specific antibodies areIgGIgM and rarelyIgA</p></li><li><p>Blood group antibodiesBlood group antibodies can be classified asNaturally occurring and immune antibodiesDepending on presensitization</p><p>Complete and incomplete antibodies Depends on agglutination of saline suspended red cellsIgM is complete antibody; most naturally occurring antibodies are complete and of IgM classIgG is incomplete antibody</p></li><li><p>Antibodies of ABO systemAnti- A</p><p>Anti- B</p><p>Anti- A1</p><p>Anti- H</p></li><li><p>Antibodies of Rh systemNaturally occurringAnti- EOccasionally anti-D and anti Cw</p><p>Immune antibodiesD antibodies are more immunogenicOther are anti c, E, e, C.Most common is anti- EAfter anti- D, anti- c is the common cause of HDN</p><p>(The vast majority of Rh antibodies are IgG and do not fix complement)</p></li><li><p>Complement Complements are series of proteins, present in plasma as an inactive precursors</p><p>When activated and react sequentially with each other they mediate destruction of cells and bacteria</p><p>Complement activation involves two stagesOpsonizationLytic stage</p></li><li><p>ComplementAntibodies can fix complement and cause rapid destruction of red cells</p><p>Destruction depends on the amount of antibody and complement</p><p>In ABO- incompatible transfusion no surviving A or B red cells can be seen after 1 hour of transfusionWhy?Remember naturally occurring Abs. are IgM and fix complement mediating the hemolysis</p></li><li><p>Disease mechanism - HDNThere is destruction of the RBCs of the fetus by antibodies produced by mother</p><p>If the fetal red cells contains the corresponding antigen, then binding of antibody will occur to red cells</p><p>Coated RBCs are removed by mononuclear phagocytic system</p></li><li><p>ConjugatedbilirubinUnconjugatedbilirubinNeonatalliver is immature andunable to handle bilirubinCoated red blood cellare hemolysed inspleen</p></li><li><p>Clinical featuresLess severe formMild anemia </p><p>Severe formsIcterus gravis neonatorum (Kernicterus)Intrauterine deathHydrops fetalisOedematous, ascites, bulky swollen &amp; friable placentaPathophysiologyExtravascular hemolysis with extramedullary erythropoiesisHepatic and cardiac failure</p></li><li><p>Hemolytic disease of newborn HDNBOFORE BIRTHAnemia (destruction of red cells)Heart failure Fetal death</p><p>AFTER BIRTHAnemia (destruction of red cells)Heart failureBuild up of bilirubinKernicterusSevere growth retardation</p></li><li><p>Rh HEMOLYTIC DISEASE OF NEWBORNAntibodies againstAnti-D and less commonly anti-c, anti-EMother is the case of anti-D is Rh -ve (negative)Firstborn infant is usually unaffectedSensitization of mother occursDuring gestationAt the time of birthAll subsequent offspring inheriting D-antigen will be affected in case of anti-D HDN</p></li><li><p>Pathogenesis</p><p>Fetomaternal Hemorrhage</p><p>Maternal Antibodies formed against Paternally derived antigens</p><p>During subsequent pregnancy, placental passage of maternal IgG antibodies</p><p>Maternal antibody attaches to fetal red blood cells</p><p>Fetal red blood cell hemolysis</p></li><li><p>Factors affecting immunization and severityAntigenic exposure</p><p>Host factors</p><p>Antibody specificity</p><p>Influence of ABO groupABO-incompatible Rh- positive cells will be hemolysed before Rh antigen can be recognized by the mothers immune system</p></li><li><p>Diagnosis and ManagementCooperation between</p><p>Pregnant patient</p><p>Obstetrician</p><p>Her spouse</p><p>Clinical laboratory</p></li><li><p>Diagnosis and Management contd.Intrauterine transfusionZone II or IIICordocentesis blood sample Hb less than 10g/dlUltrasound evidence of hydropsEarly deliveryPhototherapyNewborn transfusionExchange transfusionEffects of transfusionRemoval of bilirubinRemoval of sensitized RBCs, and antibodiesSuppression of incompatible erythropoiesis</p></li><li><p>Mechanism of actionAdministered antibodies will bind the fetal Rh- positive cellsSpleen captured these cells by Fc-receptorsSuppressor T cell response is stimulatedSpleen remove anti-D coated red cells prior to contact with antigen presenting cells antigen deviation</p></li><li><p>ABO HEMOLYTIC DISEASE OF NEW BORNFor practical purpose, only group O individuals make high titres IgG</p><p>Anti-A and anti-B are predominantly IgM</p><p>ABO antibodies are present in the sera of all individuals whose RBCs lack the corresponding antigens</p></li><li><p>ABO HDN contd.Signs and symptomsTwo mechanism protects the fetus against anti-A and anti-BRelative weak A and B antigens o fetal red cellsWidespread distribution of A &amp; B antigen in fetal tissue diverting antibodies away from fetal RBCsAnemia is most of the time mildABO- HDN may be seen in the first pregnancy</p><p>Laboratory findingsDiffer from Rh- HDN; microspherocytes are characteristic of ABO- HDNBilirubin peak is later; 1- 3 days after birthCollection of cord blood and testing eluates form red cells will reveal anti-A or anti-B</p><p>TreatmentGroup O donor blood for exchange transfusion which is rarely required</p></li></ul>